60+ Python Interview Questions and Answers to Get Your Desire Job
August 20, 2023
logicrays
The popularity of the Python language makes it in huge demand as it is functional with an array of applications. Python’s requirement is in various fields like web development, data science, and artificial intelligence. The demand for experienced Python developers is growing by heaps and bounds.
The industry hires freshers and experienced Python developers only if you can crack the interview. Brace yourselves for the questions that may come up in an interview. In this article, we will be discussing some commonly asked Python interview questions for Python developers.
It will help you to prepare for the Python interview questions and showcase your expertise in the language.
As a Python developer, you will experience an array of questions to answer with confidence and tact. There will be instances where you will have to write the code, solve a problem, or even make a new one. The idea is to be ready for all kinds of outpour. As a fresher, you can show your intern projects to earn the brownie point.
If you are somebody with experience, your previous job profile, intelligence, and answers to the questions will say it all. The pay scale for Python developers is enriching. Following are a few Python interview questions and answers to help you crack the interview.
Python Syntax uses new lines to complete a command, as opposed to other programming languages. It relies on indentation, using whitespace, to define the scope of loops, functions, and classes.
Python Certification is a sought-after skill in the programming domain. The major Python interview questions and answers need to be understood to successfully crack the interviews. Python basic interview questions and Python coding questions are an important part of any type of interview.
There are certain sought-after Python interview questions that we will be listed here. The most frequently asked questions in Python interviews include Python coding interview questions and Python programming interview questions.
Below are the Top 62 Python Developer Interview Questions:
1. What is python programming?
Python is an interpreted and high-level programming language. The general-purpose language can be used to build any type of app with the right libraries and tools. Python supports modules, objects, threads, automatic memory management, and exception handling. This helps to model real-world problems. It is used to build applications for solving problems. It has an easy-to-learn, simple, syntax that emphasizes readability. It reduces the cost of program maintenance and is capable of scripting.
2. What are the key features of the python programming language?
1. Python is an interpreted language and unlike languages like C, Python does not need to be compiled before being run.
2. Python is dynamically typed and you don’t need to state the types of variables when you declare them
3. It is well suited to object-orientated programming
4. In Python, functions can be assigned to variables
5. Writing Python code is quick but running it is often slower.
6. Python finds use in many spheres like web applications, automation, scientific modeling, and big data applications.
3. What is the use Of Python Programming Language?
Python programming language is beneficial for computation and scientific applications, web development. It is also applicable for Artificial Intelligence, Machine Learning and GUI applications. Python is also used to program all kinds of applications including; Blockchain applications. It is also used for Video, Audio, and Machine Learning apps.
It is a general-purpose language that is useful to create numerous web apps. The programming language is impactful in scripting, is open-source, and supports third-party packages. This encourages modularity and is useful for code reuse.
4. Why Python is an interpreted language?
An interpreted language is any programming language that is not in machine-level code before runtime. Therefore, Python is an interpreted language.
5. What is a python interpreter?
An interpreter reads and executes the code. Python interpreter is a stack machine that manipulates different stacks to perform various operations. It is a bytecode interpreter and the input is the instruction sets known as bytecode.
6. Is python case-sensitive?
Yes. Python is a case-sensitive language.
Python is a case-sensitive language as it differentiates lower-case and upper-case identifiers. If a user writes SUM or sum in python programming then these are considered different. Similar things can happen with the Python variables. The terms ‘helloworld’ and ‘HelloWorld’ will also be different. The programmer must name the variable as they are named. It’s best to follow Python’s naming convention to write code in a consistent format. This avoids runtime errors.
7. What is PEP 8?
PEP stands for Python Enhancement Proposal and it is a set of rules to format Python code. It improves the readability and consistency of python code.
8. What is namespace in Python?
A namespace is just a naming system. It makes sure that all the names are unique and also prevents naming conflicts.
9. What is a list in python?
The list is a data structure in python that allows you to store different types of data in it. Every value inside the list is called an item. Lists are represented as the values in between the square bracket.
10. What is the difference between lists and tuples in Python?
Below is the difference between lists and tuples:
1. Lists are mutable and can be edited while tuples are immutable
2. Lists are slower than tuples. The syntax of lists and tuples are as detailed below:
Lists Syntax: list_1 = [10, ‘Chelsea’, 20]
Tuples Syntax: tup_1 = (10, ‘Chelsea’ , 20)
11. What is PYTHONPATH?
It is an environment variable used when a module is imported. PYTHONPATH is looked up to check for the presence of the imported modules in various directories.
12. How is memory managed in Python?
Memory is managed in Python through private heap space. All Python objects and data structures are located in a private heap. The python interpreter takes care of this instead. The allocation of heap space for Python objects is done by Python’s memory manager. The core API gives access to some tools for the programmer to code.
13. In Python, what are local variables and global variables?
Global Variables are the variables declared outside a function or in global space are called global variables. A local variable is a variable that is declared inside a function.
14. Is Python a programming or scripting language?
Python is capable of scripting but it is considered a general-purpose language.
15. What is type conversion in Python?
Type conversion refers to the conversion of one data type into another.
16. What are the functions in Python?
A function is a block of code that is executed only when it is called.
17. How to install Python on Windows and set path variables?
To install Python on Windows, Install python from this link: https://www.python.org/downloads/
After this, install it on your PC. Look for the location where PYTHON has been installed on your PC using the following command on your command prompt: cmd python.
Then go to advanced system settings and add a new variable and name it as PYTHON_NAME and paste the copied path.
Look for the path variable, select its value and select ‘edit’.
18. Is indentation required in python?
Indentation is necessary for Python as it specifies a block of code. All code within loops, classes, functions, etc. is specified within an indented block.
19. What is the difference between Python Arrays and lists?
In Python, Arrays and Lists have the same way of storing data. Arrays can hold single data type elements and lists can hold any data type elements.
20. How to comment on multiple lines in python?
All the lines that are to be commented are prefixed by a #. All you need is to hold the ctrl key and left-click in every place wherever you want to include a # character. This will comment on all the lines where the cursor is introduced
21. What is pickling and unpickling?
Pickle module accepts a Python object and converts it into a string representation then dumps it into a file through dump function. The process of retrieving original Python objects from the stored string representation is called unpickling.
22. In Python, what are the generators?
Generators are functions that return an iterable set of items.
23. How will you capitalize the first letter of string?
The capitalize () method capitalizes the first letter of a string.
24. What are strings in python?
In Python, strings are arrays that represent the sequence of characters. You can use square brackets to access the elements of a string. Once a string is defined then you cannot change them.
25. What are docstrings in Python?
Docstrings are documentation strings. These docstrings are within triple quotes and these are not assigned to any variable.
26. What are Python packages?
Python packages are namespaces containing multiple modules.
27. How can files be deleted in Python?
To delete a file in Python, you need to use the os. remove() function.
28. Does Python have OOps concepts?
Python is an object-oriented programming language. This means that any program can be solved in python by creating an object model. However, Python can be treated as procedural as well as structural language.
29. What is split used for?
The split() method is used to separate a given string in Python.
30. What are python modules? Name some commonly used built-in modules in Python?
Python modules are files that contain Python code. This code can be function classes or variables.
Some of the commonly used modules are:
os
sys
math
random
data time
JSON
31. What is dict in python?
It is a collection of data that is used to store data values. It is a built-in function and is also known as an associative array in other programming languages.
32. What is a pass in Python?
A Pass statement is a null operation and nothing happens when it is executed. It is used for making the code syntactically correct.
33. What are the limitations of python?
It is slow compared to other programming languages like C/C++ or Java.
Python is weak for mobile development and hence it is not preferred.
Memory consumption is also high in python.
Python also has design restrictions.
34. What are positive and negative indices?
When positive indices are applied then the search begins from left to right whereas when negative indices are applied then the search begins from right to left.
35. What is the use of relational, assignment, and membership operators in python?
1. Relational operators – They are used to compare values
2. Assignment operators – They are used to assign value to the variables
3. Membership operators – It validates the membership of a value.
36. What is the index in python?
Index refers to a position in a list or string. The string is a list of characters and you access them with the help of an index.
37. What is the lambda function in python?
You can create an anonymous function with the help of the lambda function. It can accept any number of arguments but it can only have one statement.
38. What are the libraries of python that are used for Artificial intelligence and Machine learning?
Various libraries used for the development of AI and ML are,
SciPy
NumPy
PyBrain
Sickit-learn, etc.
39. What is self in python?
Self represents the object of a class. You can differentiate between attributes and methods of the class with the help of self.
40. What is the difference between .py and .pyc files?
.py contains the source code of a program and .pyc has the bytecode of a program. Bytecode is obtained after the compilation of .pyfiiles.
41. What are the different types of operators in python?
Every operator is used for performing a different set of operations. The list of various operators are as follows:
1. Assignment operators
2. Identity operators
3. Bitwise operators
4. Logical operators
5. Membership operators
6. Comparison operators, etc.
42. What are decorators in python?
A Python decorator is a specific modification that we make in code syntax to alter Python functions easily.
43. What is Lambda’s expression?
Lambda expression is an anonymous function that is often used as an inline function in Python code.
44. Why don’t lambda forms in python have statements?
Lamda form is used to make new function objects and then return them during the runtime, for that reason Lambda forms do not have statements.
45. What are iterators in python?
In Python, iterators are used to iterate over iterable objects such as lists, tuples, dicts, and sets.
46. What is scope in python?
Every object in python remains relevant in a specific area that is defined to it, which is called scope. There are different type of scope that are created during code execution in python and that is,
1. Local scope
2. Global scope
3. Module-level scope
4. Outermost scope
47. What are Stop Words in Python? Explain with examples.
There is a provision to filter stopwords in Python language. Natural Language Processing presents challenges like natural language understanding. Text can contain stop words like ‘is’, ‘the’, and ‘are’. Stop words can be filtered from the text. The nltk module contains a list of stop words.
48. Define Conditional Expressions
In Python, a conditional expression is a shorthand way of writing an if-else statement. It is also known as a ternary operator because it takes three arguments:
The first argument, a condition,
The second argument where the expression to execute if the condition is true,
A third argument is where the expression runs when the condition is false.
Conditional expression syntax can be as follows:
value_if_true if condition else value_if_false
For example:
x = 5
y = 10
print("x is greater than y")
if x > y else print("y is greater than x")
The output will be "y is greater than x" It is useful to simplify simple if-else statements, making the code more readable and efficient.
It is a commonly used syntax for the Conditional expression (Ternary operator) in Python programming. It is a standard way of writing a ternary operator.
49. What are the differences between function and recursion?
It is one of the vital Python viva questions which the interviewer seeks for the answer. Your answer should reflect your thought process. It is how you can prove so-
In Python, a function is a block of code reusable throughout a program. Functions are defined using the “def” keyword and can accept input parameters and return output.
Recursion, on the other hand, is a technique where a function calls itself. A recursive function has a base case, which defines when the recursion should stop, and a recursive case, which shows how the function should call itself. Recursion solves problems into smaller sub-problems.
Functions are defined for a specific task, whereas recursion is a technique used to solve a problem. The main difference between function and recursion is that a function can call other functions but does not call itself, while a recursive function calls itself to solve a problem. Recursive functions are less efficient than iterative functions because they consume more memory and computational power.
50. How does Python handle inheritance?
In Python, inheritance is a mechanism that allows a new class to inherit the properties and methods of an existing course. The new class reuses the current code and extends it to meet its requirements.
Python supports single inheritance, where a class can inherit from only one parent class, and multiple inheritances, where a class can inherit from multiple parent classes. Inheritance allows for code reuse and modularity, making the code more readable and maintainable.
51. What is the difference between multi-threading and multi-processing in Python?
Multithreading in Python allows multiple threads to run concurrently within a process, sharing memory and other resources. These threads can communicate and synchronize using locks, semaphores, and other synchronization primitives. Multi-processing allows multiple processing to run concurrently, each with its memory and resources, potentially on different cores or machines.
The processes can communicate with each other using inter-process communication (IPC) mechanisms such as pipes, sockets, and shared memory. Multithreading is useful for parallelizing CPU-bound tasks. Multi-processing is useful for parallelizing both CPU-bound and I/O-bound tasks.
52. What is slicing in Python?
Slicing in Python is extracting a portion of a sequence, such as a string, list, or tuple. The syntax for slicing is sequence[start:stop: step], where the start is the index of the first element to include, the stop is the index of the first element to exclude, and the step is the number of indices between elements. So,
If the start is not specified, it defaults to the beginning of the sequence.
If the stop is not specified, it defaults to the end of the sequence.
It defaults to 1 when the step is unspecified.
Slicing extracts substrings, sublists, and sub-tuples. It reverses a sequence by specifying a negative step.
53. What is the difference between range & xrange?
It is a typical Python interview question for freshers. You can crack this in less than a minute when your basics are straightforward. It is how you can share your insight-
In Python 2, range generates a list of numbers, while xrange generates an object that iterates to produce the numbers. The main difference is that range creates the entire list in memory, which can be very memory-intensive for large fields, while xrange generates the numbers on the fly, which is more memory-efficient.
In Python 3, xrange is no longer a separate function, and the range function behaves as xrange did in Python 2. It generates an iterator rather than a list.
54. How can you generate random numbers?
One can generate random numbers with the most commonly used module- random, which provides functions such as random(), randint(), randrange(), uniform(), and others to generate various types of random numbers. Another random module from numpy library provides similar functions.
Python also has a built-in random module to generate random numbers. It is advisable to use a random module for most cases as it is the most widely used.
55. How to debug a python program?
One can opt for diverse ways to debug a Python program:
1. Using print statements: Inserting print statements in strategic locations in the code can help identify where the problem is occurring and know the values of variables at different points in the program.
2. Using the built-in pdb module: It is an interactive source code debugger for Python programs. It invokes by running the command python -m pdb script.py. Using an external debugger: Popular IDEs like PyCharm, VSCode, and Eclipse have built-in debuggers to step through the code, set breakpoints, and inspect variables.
3. Using a logging library: Python logging library enables logging messages from the program for debugging and understanding what the program is doing.
4. Using assert statement: This statement checks whether the given condition is true. If the condition is false, it raises an exception, and the program stops at that point.
56. How does a function return values?
The above is a basic Python interview question asked to every candidate. The knack is to answer it with an assertion like the following-
In Python, a function returns a value using the return statement. The value or expression following the return keyword is the value returned to the caller. It will be a return None by default when a function has no return statement.
Multiple values are returnable using the tuple packing and *args or **kwargs in the return statement. Functions can also return other functions, classes, and objects, allowing for more complex and powerful code structures.
57. What are Python libraries? Name a few of them.
Python libraries are pre-written collections of code imported into a Python program. They add functionality. Some popular libraries include NumPy for numerical computing, pandas for data manipulation, and Matplotlib for data visualization. Other libraries have TensorFlow, Scikit-learn, Keras for machine learning, and Selenium for web scraping.
58. What are data frames?
A data frame in Python is a two-dimensional data structure to store and manipulate data in a tabular format. It is similar to a spreadsheet or a SQL table and is often used with the pandas library to load, manage, and analyze large datasets. Data frame creation is from different sources, including CSV files, Excel files, and SQL databases.
59. Explain Inheritance in Python with an example
Inheritance is a way to create a new class that is a modified version of an existing course. The subclass is a new class, while Superclass is the current class. The subclass inherits attributes and methods from the superclass but can also have additional attributes and methods.
For example, let’s say we have a class called “Animal” that has an attribute called “name” and a method called “speak.” We can create a subclass called “Dogs” that inherits the attributes and methods from the “Animals” class, but also has an additional attribute called “breed” and a new method called “bark”.
class Animals:
def __init__(self, name):
self.name = name
def speak(self):
pass
class Dogs(Animals):
def __init__(self, name, breed):
super().__init__(name)
self.breed = breed
def bark(self):
print("Woof woof")
dog = Dogs("Fido," "Golden Retriever")
print(dog.name) # Output: "Fido"
print(dog.breed) # Output: "Golden Retriever"
dog.speak() # Inherited from superclass
dog.bark() # Output: "Woof woof"
The super() function usage is to call the init method of the superclass within the subclass. It is valuable to inherit the attributes of the superclass.
60. What is __init__ in Python?
Questions on _init_ is a part of Python interview questions and answers for experienced. The interviewer looks forward to an explanation, an example, and the inference you conclude.
What we know as a constructor is a __init__ in Python classes. It is called by design when there is a class object created. The __init__ method is used to initialize the object’s attributes and to do any other necessary setup.
The __init__ method has a particular parameter called self, which refers to the object’s creativity. Any attributes or variables initialization for the object should be passed as arguments to the __init__ method and then assigned to self.
For example, the following class has a __init__ method that takes two arguments, name and age, and assigns them to the object’s name and age attributes:
class Person:
def __init__(self, name, age):
self.name = name
self.age = age
person = Person("John", 30)
print(person.name) # Output: "John"
print(person.age) # Output: 30
The __init__ method is called automatically when you create a new object of the class, it initializes the attributes of the object with the values passed in.
If you don't define a __init__ method in a class, Python will provide a default one that does nothing.
61. Define encapsulation in Python
Encapsulation is a principle of object-oriented programming that allows you to hide the internal implementation details of a class from the outside world. In Python, encapsulation is achievable using private and protected methods and attributes.
An attribute or method is private by prefixing its name with two underscores(__). It indicates that the attribute or method should not be accessed or modified outside the class. For example:
class MyClass:
def __init__(self):
self.__private_attr = "I am private"
def __private_method(self):
print("I am private too")
def public_method(self):
print(self.__private_attr)
self.__private_method()
obj = MyClass()
obj.public_method()
# prints: I am private
# I am private too
print(obj.__private_attr)
# AttributeError: 'MyClass' object has no attribute '__private_attr'
It is not recommended to access these private attributes or methods directly, and it’s not a good practice to do so.
A protected attribute or method is protected by prefixing its name with a single underscore(_).
Encapsulation hides the internal implementation details of a class from other parts of the program to prevent direct access or modification of the class’s data. It helps to create stable and predictable code by reducing the risk of bugs and allows the class’s implementation to change without affecting the code that uses it.
62. What is multithreading?
Multithreading is a way of achieving concurrent execution of multiple threads in a single process. Each thread runs independently of the others, with its program counter, stack, and local variables. Threads share the same memory space, which allows them to share data and communicate with each other.
Multithreading improves the performance of a program by allowing different parts of it to run in parallel. It can be particularly useful for programs that perform I/O operations to process data while waiting for input or output to complete. Multithreading also improves the program’s responsiveness by performing background tasks while waiting for user input.
All the above questions are usually a part of Python interview programs and can be learned extensively by freshers and developers. LogicRays Academy provides you 100% guarantee for job placement by training students on live projects. Contact Us to start your career in Python.
